Prophylactic anticoagulation after minimally invasive hysterectomy for endometrial cancer: a cost-effectiveness analysis

Abstract

Objective To determine our institutional rate of venous thromboembolism (VTE) following minimally invasive surgery for endometrial cancer and to perform a cost-effectiveness analysis of extended prophylactic anticoagulation after minimally invasive staging surgery for endometrial cancer. Methods All patients with newly diagnosed endometrial cancer who underwent minimally invasive staging surgery from January 1, 2017 to December 31, 2020 were identified retrospectively, and clinicopathologic and outcome data were obtained through chart review. Event probabilities and utility decrements were obtained through published clinical data and literature review. A decision model was created to compare 28 days of no post-operative pharmacologic prophylaxis, prophylactic enoxaparin, and prophylactic apixaban. Outcomes included no complications, deep vein thrombosis (DVT), pulmonary embolism, clinically relevant non-major bleeding, and major bleeding. We assumed a willingness-to-pay threshold of $100 000 per quality-adjusted life year (QALY) gained. Results Three of 844 patients (0.36%) had a VTE following minimally invasive staging surgery for endometrial cancer. In this model, no pharmacologic prophylaxis was less costly and more effective than prophylactic apixaban and prophylactic enoxaparin over all parameters examined. When all patients were assigned prophylaxis, prophylactic apixaban was both less costly and more effective than prophylactic enoxaparin. If the risk of DVT was ≥4.8%, prophylactic apixaban was favored over no pharmacologic prophylaxis. On Monte Carlo probabilistic sensitivity analysis for the base case scenario, no pharmacologic prophylaxis was favored in 41.1% of iterations at a willingness-to-pay threshold of $100 000 per QALY. Conclusions In this cost-effectiveness model, no extended pharmacologic anticoagulation was superior to extended prophylactic enoxaparin and apixaban in clinically early-stage endometrial cancer patients undergoing minimally invasive surgery. This model supports use of prophylactic apixaban for 7 days post-operatively in select patients when the risk of DVT is 4.8% or higher.